Commit | Line | Data |
---|---|---|
bcb877e4 | 1 | /* |
b5e89ed5 | 2 | * \file drm_fops.c |
1da177e4 | 3 | * File operations for DRM |
b5e89ed5 | 4 | * |
1da177e4 LT |
5 | * \author Rickard E. (Rik) Faith <faith@valinux.com> |
6 | * \author Daryll Strauss <daryll@valinux.com> | |
7 | * \author Gareth Hughes <gareth@valinux.com> | |
8 | */ | |
9 | ||
10 | /* | |
11 | * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com | |
12 | * | |
13 | * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. | |
14 | * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. | |
15 | * All Rights Reserved. | |
16 | * | |
17 | * Permission is hereby granted, free of charge, to any person obtaining a | |
18 | * copy of this software and associated documentation files (the "Software"), | |
19 | * to deal in the Software without restriction, including without limitation | |
20 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
21 | * and/or sell copies of the Software, and to permit persons to whom the | |
22 | * Software is furnished to do so, subject to the following conditions: | |
23 | * | |
24 | * The above copyright notice and this permission notice (including the next | |
25 | * paragraph) shall be included in all copies or substantial portions of the | |
26 | * Software. | |
27 | * | |
28 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
29 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
30 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
31 | * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR | |
32 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, | |
33 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR | |
34 | * OTHER DEALINGS IN THE SOFTWARE. | |
35 | */ | |
36 | ||
760285e7 | 37 | #include <drm/drmP.h> |
1da177e4 | 38 | #include <linux/poll.h> |
5a0e3ad6 | 39 | #include <linux/slab.h> |
e0cd3608 | 40 | #include <linux/module.h> |
e7b96070 | 41 | #include "drm_legacy.h" |
67d0ec4e | 42 | #include "drm_internal.h" |
1da177e4 | 43 | |
0d639883 | 44 | /* from BKL pushdown */ |
58374713 AB |
45 | DEFINE_MUTEX(drm_global_mutex); |
46 | ||
bcb877e4 DV |
47 | /** |
48 | * DOC: file operations | |
49 | * | |
50 | * Drivers must define the file operations structure that forms the DRM | |
51 | * userspace API entry point, even though most of those operations are | |
52 | * implemented in the DRM core. The mandatory functions are drm_open(), | |
53 | * drm_read(), drm_ioctl() and drm_compat_ioctl if CONFIG_COMPAT is enabled. | |
54 | * Drivers which implement private ioctls that require 32/64 bit compatibility | |
55 | * support must provided their onw .compat_ioctl() handler that processes | |
56 | * private ioctls and calls drm_compat_ioctl() for core ioctls. | |
57 | * | |
58 | * In addition drm_read() and drm_poll() provide support for DRM events. DRM | |
59 | * events are a generic and extensible means to send asynchronous events to | |
60 | * userspace through the file descriptor. They are used to send vblank event and | |
61 | * page flip completions by the KMS API. But drivers can also use it for their | |
62 | * own needs, e.g. to signal completion of rendering. | |
63 | * | |
64 | * The memory mapping implementation will vary depending on how the driver | |
65 | * manages memory. Legacy drivers will use the deprecated drm_legacy_mmap() | |
66 | * function, modern drivers should use one of the provided memory-manager | |
67 | * specific implementations. For GEM-based drivers this is drm_gem_mmap(). | |
68 | * | |
69 | * No other file operations are supported by the DRM userspace API. Overall the | |
da5335b8 | 70 | * following is an example #file_operations structure:: |
bcb877e4 DV |
71 | * |
72 | * static const example_drm_fops = { | |
73 | * .owner = THIS_MODULE, | |
74 | * .open = drm_open, | |
75 | * .release = drm_release, | |
76 | * .unlocked_ioctl = drm_ioctl, | |
77 | * #ifdef CONFIG_COMPAT | |
78 | * .compat_ioctl = drm_compat_ioctl, | |
79 | * #endif | |
80 | * .poll = drm_poll, | |
81 | * .read = drm_read, | |
82 | * .llseek = no_llseek, | |
83 | * .mmap = drm_gem_mmap, | |
84 | * }; | |
85 | */ | |
86 | ||
1dcc0ceb | 87 | static int drm_open_helper(struct file *filp, struct drm_minor *minor); |
c94f7029 | 88 | |
84b1fd10 | 89 | static int drm_setup(struct drm_device * dev) |
1da177e4 | 90 | { |
1da177e4 LT |
91 | int ret; |
92 | ||
7d14bb6b DV |
93 | if (dev->driver->firstopen && |
94 | !drm_core_check_feature(dev, DRIVER_MODESET)) { | |
22eae947 | 95 | ret = dev->driver->firstopen(dev); |
b5e89ed5 | 96 | if (ret != 0) |
1da177e4 LT |
97 | return ret; |
98 | } | |
99 | ||
f336ab76 DV |
100 | ret = drm_legacy_dma_setup(dev); |
101 | if (ret < 0) | |
102 | return ret; | |
1da177e4 | 103 | |
1da177e4 | 104 | |
b5e89ed5 | 105 | DRM_DEBUG("\n"); |
1da177e4 LT |
106 | return 0; |
107 | } | |
108 | ||
109 | /** | |
bcb877e4 DV |
110 | * drm_open - open method for DRM file |
111 | * @inode: device inode | |
112 | * @filp: file pointer. | |
b5e89ed5 | 113 | * |
bcb877e4 DV |
114 | * This function must be used by drivers as their .open() #file_operations |
115 | * method. It looks up the correct DRM device and instantiates all the per-file | |
116 | * resources for it. | |
117 | * | |
118 | * RETURNS: | |
1da177e4 | 119 | * |
bcb877e4 | 120 | * 0 on success or negative errno value on falure. |
1da177e4 | 121 | */ |
b5e89ed5 | 122 | int drm_open(struct inode *inode, struct file *filp) |
1da177e4 | 123 | { |
1616c525 | 124 | struct drm_device *dev; |
2c14f28b | 125 | struct drm_minor *minor; |
1616c525 | 126 | int retcode; |
fdb40a08 | 127 | int need_setup = 0; |
b5e89ed5 | 128 | |
1616c525 DH |
129 | minor = drm_minor_acquire(iminor(inode)); |
130 | if (IS_ERR(minor)) | |
131 | return PTR_ERR(minor); | |
2c07a21d | 132 | |
1616c525 | 133 | dev = minor->dev; |
fdb40a08 IH |
134 | if (!dev->open_count++) |
135 | need_setup = 1; | |
fdb40a08 | 136 | |
6796cb16 DH |
137 | /* share address_space across all char-devs of a single device */ |
138 | filp->f_mapping = dev->anon_inode->i_mapping; | |
fdb40a08 | 139 | |
1dcc0ceb | 140 | retcode = drm_open_helper(filp, minor); |
fdb40a08 IH |
141 | if (retcode) |
142 | goto err_undo; | |
fdb40a08 IH |
143 | if (need_setup) { |
144 | retcode = drm_setup(dev); | |
145 | if (retcode) | |
146 | goto err_undo; | |
f453ba04 | 147 | } |
fdb40a08 | 148 | return 0; |
a2c0a97b | 149 | |
fdb40a08 | 150 | err_undo: |
fdb40a08 | 151 | dev->open_count--; |
1616c525 | 152 | drm_minor_release(minor); |
1da177e4 LT |
153 | return retcode; |
154 | } | |
155 | EXPORT_SYMBOL(drm_open); | |
156 | ||
bcb877e4 | 157 | /* |
d985c108 DA |
158 | * Check whether DRI will run on this CPU. |
159 | * | |
160 | * \return non-zero if the DRI will run on this CPU, or zero otherwise. | |
161 | */ | |
162 | static int drm_cpu_valid(void) | |
163 | { | |
d985c108 DA |
164 | #if defined(__sparc__) && !defined(__sparc_v9__) |
165 | return 0; /* No cmpxchg before v9 sparc. */ | |
166 | #endif | |
167 | return 1; | |
168 | } | |
169 | ||
bcb877e4 | 170 | /* |
d985c108 DA |
171 | * Called whenever a process opens /dev/drm. |
172 | * | |
d985c108 | 173 | * \param filp file pointer. |
f4aede2e | 174 | * \param minor acquired minor-object. |
d985c108 DA |
175 | * \return zero on success or a negative number on failure. |
176 | * | |
177 | * Creates and initializes a drm_file structure for the file private data in \p | |
178 | * filp and add it into the double linked list in \p dev. | |
179 | */ | |
1dcc0ceb | 180 | static int drm_open_helper(struct file *filp, struct drm_minor *minor) |
d985c108 | 181 | { |
f4aede2e | 182 | struct drm_device *dev = minor->dev; |
84b1fd10 | 183 | struct drm_file *priv; |
d985c108 DA |
184 | int ret; |
185 | ||
186 | if (filp->f_flags & O_EXCL) | |
187 | return -EBUSY; /* No exclusive opens */ | |
188 | if (!drm_cpu_valid()) | |
189 | return -EINVAL; | |
13bb9cc8 | 190 | if (dev->switch_power_state != DRM_SWITCH_POWER_ON && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF) |
5bcf719b | 191 | return -EINVAL; |
d985c108 | 192 | |
f4aede2e | 193 | DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index); |
d985c108 | 194 | |
6ebc22e6 | 195 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
d985c108 DA |
196 | if (!priv) |
197 | return -ENOMEM; | |
198 | ||
d985c108 | 199 | filp->private_data = priv; |
6c340eac | 200 | priv->filp = filp; |
2df68b43 | 201 | priv->uid = current_euid(); |
5fce5e0b | 202 | priv->pid = get_pid(task_pid(current)); |
f4aede2e | 203 | priv->minor = minor; |
df9b6a9c | 204 | |
d985c108 | 205 | /* for compatibility root is always authenticated */ |
3cb01a98 | 206 | priv->authenticated = capable(CAP_SYS_ADMIN); |
d985c108 DA |
207 | priv->lock_count = 0; |
208 | ||
bd1b331f | 209 | INIT_LIST_HEAD(&priv->lhead); |
f453ba04 | 210 | INIT_LIST_HEAD(&priv->fbs); |
4b096ac1 | 211 | mutex_init(&priv->fbs_lock); |
e2f5d2ea | 212 | INIT_LIST_HEAD(&priv->blobs); |
681047b4 | 213 | INIT_LIST_HEAD(&priv->pending_event_list); |
c9a9c5e0 KH |
214 | INIT_LIST_HEAD(&priv->event_list); |
215 | init_waitqueue_head(&priv->event_wait); | |
216 | priv->event_space = 4096; /* set aside 4k for event buffer */ | |
bd1b331f | 217 | |
9b2c0b7f CW |
218 | mutex_init(&priv->event_read_lock); |
219 | ||
1bcecfac | 220 | if (drm_core_check_feature(dev, DRIVER_GEM)) |
673a394b EA |
221 | drm_gem_open(dev, priv); |
222 | ||
3248877e DA |
223 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
224 | drm_prime_init_file_private(&priv->prime); | |
225 | ||
d985c108 DA |
226 | if (dev->driver->open) { |
227 | ret = dev->driver->open(dev, priv); | |
228 | if (ret < 0) | |
df9b6a9c | 229 | goto out_prime_destroy; |
d985c108 DA |
230 | } |
231 | ||
2cbae7e6 DV |
232 | if (drm_is_primary_client(priv)) { |
233 | ret = drm_master_open(priv); | |
a0af2e53 | 234 | if (ret) |
df9b6a9c | 235 | goto out_close; |
7c1c2871 | 236 | } |
bd1b331f | 237 | |
1d2ac403 | 238 | mutex_lock(&dev->filelist_mutex); |
bd1b331f | 239 | list_add(&priv->lhead, &dev->filelist); |
1d2ac403 | 240 | mutex_unlock(&dev->filelist_mutex); |
d985c108 DA |
241 | |
242 | #ifdef __alpha__ | |
243 | /* | |
244 | * Default the hose | |
245 | */ | |
246 | if (!dev->hose) { | |
247 | struct pci_dev *pci_dev; | |
248 | pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); | |
249 | if (pci_dev) { | |
250 | dev->hose = pci_dev->sysdata; | |
251 | pci_dev_put(pci_dev); | |
252 | } | |
253 | if (!dev->hose) { | |
59c1ad3b YW |
254 | struct pci_bus *b = list_entry(pci_root_buses.next, |
255 | struct pci_bus, node); | |
d985c108 DA |
256 | if (b) |
257 | dev->hose = b->sysdata; | |
258 | } | |
259 | } | |
260 | #endif | |
261 | ||
262 | return 0; | |
df9b6a9c SWK |
263 | |
264 | out_close: | |
265 | if (dev->driver->postclose) | |
266 | dev->driver->postclose(dev, priv); | |
267 | out_prime_destroy: | |
268 | if (drm_core_check_feature(dev, DRIVER_PRIME)) | |
269 | drm_prime_destroy_file_private(&priv->prime); | |
1bcecfac | 270 | if (drm_core_check_feature(dev, DRIVER_GEM)) |
df9b6a9c | 271 | drm_gem_release(dev, priv); |
df9b6a9c | 272 | put_pid(priv->pid); |
9a298b2a | 273 | kfree(priv); |
d985c108 DA |
274 | filp->private_data = NULL; |
275 | return ret; | |
276 | } | |
277 | ||
c9a9c5e0 KH |
278 | static void drm_events_release(struct drm_file *file_priv) |
279 | { | |
280 | struct drm_device *dev = file_priv->minor->dev; | |
281 | struct drm_pending_event *e, *et; | |
c9a9c5e0 KH |
282 | unsigned long flags; |
283 | ||
284 | spin_lock_irqsave(&dev->event_lock, flags); | |
285 | ||
681047b4 DV |
286 | /* Unlink pending events */ |
287 | list_for_each_entry_safe(e, et, &file_priv->pending_event_list, | |
288 | pending_link) { | |
289 | list_del(&e->pending_link); | |
290 | e->file_priv = NULL; | |
291 | } | |
292 | ||
c9a9c5e0 | 293 | /* Remove unconsumed events */ |
1dda6805 YC |
294 | list_for_each_entry_safe(e, et, &file_priv->event_list, link) { |
295 | list_del(&e->link); | |
1b47aaf9 | 296 | kfree(e); |
1dda6805 | 297 | } |
c9a9c5e0 KH |
298 | |
299 | spin_unlock_irqrestore(&dev->event_lock, flags); | |
300 | } | |
301 | ||
bcb877e4 | 302 | /* |
1c8887dd DH |
303 | * drm_legacy_dev_reinit |
304 | * | |
305 | * Reinitializes a legacy/ums drm device in it's lastclose function. | |
306 | */ | |
307 | static void drm_legacy_dev_reinit(struct drm_device *dev) | |
308 | { | |
68dfbeba DV |
309 | if (dev->irq_enabled) |
310 | drm_irq_uninstall(dev); | |
311 | ||
312 | mutex_lock(&dev->struct_mutex); | |
313 | ||
314 | drm_legacy_agp_clear(dev); | |
315 | ||
316 | drm_legacy_sg_cleanup(dev); | |
317 | drm_legacy_vma_flush(dev); | |
318 | drm_legacy_dma_takedown(dev); | |
319 | ||
320 | mutex_unlock(&dev->struct_mutex); | |
1c8887dd | 321 | |
1c8887dd DH |
322 | dev->sigdata.lock = NULL; |
323 | ||
324 | dev->context_flag = 0; | |
325 | dev->last_context = 0; | |
326 | dev->if_version = 0; | |
68dfbeba DV |
327 | |
328 | DRM_DEBUG("lastclose completed\n"); | |
1c8887dd DH |
329 | } |
330 | ||
bcb877e4 | 331 | /* |
1c8887dd DH |
332 | * Take down the DRM device. |
333 | * | |
334 | * \param dev DRM device structure. | |
335 | * | |
336 | * Frees every resource in \p dev. | |
337 | * | |
338 | * \sa drm_device | |
339 | */ | |
68dfbeba | 340 | void drm_lastclose(struct drm_device * dev) |
1c8887dd | 341 | { |
1c8887dd DH |
342 | DRM_DEBUG("\n"); |
343 | ||
344 | if (dev->driver->lastclose) | |
345 | dev->driver->lastclose(dev); | |
346 | DRM_DEBUG("driver lastclose completed\n"); | |
347 | ||
68dfbeba DV |
348 | if (!drm_core_check_feature(dev, DRIVER_MODESET)) |
349 | drm_legacy_dev_reinit(dev); | |
1c8887dd DH |
350 | } |
351 | ||
1da177e4 | 352 | /** |
bcb877e4 DV |
353 | * drm_release - release method for DRM file |
354 | * @inode: device inode | |
355 | * @filp: file pointer. | |
1da177e4 | 356 | * |
bcb877e4 DV |
357 | * This function must be used by drivers as their .release() #file_operations |
358 | * method. It frees any resources associated with the open file, and if this is | |
359 | * the last open file for the DRM device also proceeds to call drm_lastclose(). | |
1da177e4 | 360 | * |
bcb877e4 DV |
361 | * RETURNS: |
362 | * | |
363 | * Always succeeds and returns 0. | |
1da177e4 | 364 | */ |
b5e89ed5 | 365 | int drm_release(struct inode *inode, struct file *filp) |
1da177e4 | 366 | { |
6c340eac | 367 | struct drm_file *file_priv = filp->private_data; |
1616c525 DH |
368 | struct drm_minor *minor = file_priv->minor; |
369 | struct drm_device *dev = minor->dev; | |
1da177e4 | 370 | |
58374713 | 371 | mutex_lock(&drm_global_mutex); |
1da177e4 | 372 | |
b5e89ed5 | 373 | DRM_DEBUG("open_count = %d\n", dev->open_count); |
1da177e4 | 374 | |
1d2ac403 | 375 | mutex_lock(&dev->filelist_mutex); |
dff01de1 | 376 | list_del(&file_priv->lhead); |
1d2ac403 DV |
377 | mutex_unlock(&dev->filelist_mutex); |
378 | ||
379 | mutex_lock(&dev->struct_mutex); | |
32e7b94a DH |
380 | if (file_priv->magic) |
381 | idr_remove(&file_priv->master->magic_map, file_priv->magic); | |
dff01de1 CW |
382 | mutex_unlock(&dev->struct_mutex); |
383 | ||
22eae947 | 384 | if (dev->driver->preclose) |
6c340eac | 385 | dev->driver->preclose(dev, file_priv); |
1da177e4 LT |
386 | |
387 | /* ======================================================== | |
388 | * Begin inline drm_release | |
389 | */ | |
390 | ||
b5e89ed5 | 391 | DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", |
ba25f9dc | 392 | task_pid_nr(current), |
5817878c | 393 | (long)old_encode_dev(file_priv->minor->kdev->devt), |
b5e89ed5 DA |
394 | dev->open_count); |
395 | ||
1a75a222 DV |
396 | if (!drm_core_check_feature(dev, DRIVER_MODESET)) |
397 | drm_legacy_lock_release(dev, filp); | |
1da177e4 | 398 | |
67cb4b4d | 399 | if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) |
a266162a | 400 | drm_legacy_reclaim_buffers(dev, file_priv); |
67cb4b4d | 401 | |
c9a9c5e0 KH |
402 | drm_events_release(file_priv); |
403 | ||
e2f5d2ea | 404 | if (drm_core_check_feature(dev, DRIVER_MODESET)) { |
ea39f835 | 405 | drm_fb_release(file_priv); |
e2f5d2ea DS |
406 | drm_property_destroy_user_blobs(dev, file_priv); |
407 | } | |
ea39f835 | 408 | |
1bcecfac | 409 | if (drm_core_check_feature(dev, DRIVER_GEM)) |
4e47e02d P |
410 | drm_gem_release(dev, file_priv); |
411 | ||
e7b96070 | 412 | drm_legacy_ctxbitmap_flush(dev, file_priv); |
1da177e4 | 413 | |
c996fd0b | 414 | mutex_lock(&dev->master_mutex); |
7c1c2871 | 415 | |
7963e9db | 416 | if (file_priv->is_master) { |
fda714c2 | 417 | struct drm_master *master = file_priv->master; |
bd1b331f | 418 | |
bcb877e4 | 419 | /* |
fda714c2 TH |
420 | * Since the master is disappearing, so is the |
421 | * possibility to lock. | |
422 | */ | |
3cb01a98 | 423 | mutex_lock(&dev->struct_mutex); |
fda714c2 TH |
424 | if (master->lock.hw_lock) { |
425 | if (dev->sigdata.lock == master->lock.hw_lock) | |
426 | dev->sigdata.lock = NULL; | |
427 | master->lock.hw_lock = NULL; | |
428 | master->lock.file_priv = NULL; | |
429 | wake_up_interruptible_all(&master->lock.lock_queue); | |
430 | } | |
c996fd0b | 431 | mutex_unlock(&dev->struct_mutex); |
fda714c2 | 432 | |
7c1c2871 DA |
433 | if (file_priv->minor->master == file_priv->master) { |
434 | /* drop the reference held my the minor */ | |
862302ff TH |
435 | if (dev->driver->master_drop) |
436 | dev->driver->master_drop(dev, file_priv, true); | |
7c1c2871 DA |
437 | drm_master_put(&file_priv->minor->master); |
438 | } | |
1da177e4 | 439 | } |
7c1c2871 | 440 | |
c996fd0b | 441 | /* drop the master reference held by the file priv */ |
1793126f DH |
442 | if (file_priv->master) |
443 | drm_master_put(&file_priv->master); | |
7963e9db | 444 | file_priv->is_master = 0; |
c996fd0b TH |
445 | mutex_unlock(&dev->master_mutex); |
446 | ||
22eae947 | 447 | if (dev->driver->postclose) |
6c340eac | 448 | dev->driver->postclose(dev, file_priv); |
3248877e | 449 | |
319c933c | 450 | |
3248877e DA |
451 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
452 | drm_prime_destroy_file_private(&file_priv->prime); | |
453 | ||
ddde4371 VS |
454 | WARN_ON(!list_empty(&file_priv->event_list)); |
455 | ||
5fce5e0b | 456 | put_pid(file_priv->pid); |
9a298b2a | 457 | kfree(file_priv); |
1da177e4 LT |
458 | |
459 | /* ======================================================== | |
460 | * End inline drm_release | |
461 | */ | |
462 | ||
b5e89ed5 | 463 | if (!--dev->open_count) { |
68dfbeba | 464 | drm_lastclose(dev); |
2c07a21d DA |
465 | if (drm_device_is_unplugged(dev)) |
466 | drm_put_dev(dev); | |
1da177e4 | 467 | } |
58374713 | 468 | mutex_unlock(&drm_global_mutex); |
1da177e4 | 469 | |
1616c525 DH |
470 | drm_minor_release(minor); |
471 | ||
68dfbeba | 472 | return 0; |
1da177e4 LT |
473 | } |
474 | EXPORT_SYMBOL(drm_release); | |
475 | ||
bcb877e4 DV |
476 | /** |
477 | * drm_read - read method for DRM file | |
478 | * @filp: file pointer | |
479 | * @buffer: userspace destination pointer for the read | |
480 | * @count: count in bytes to read | |
481 | * @offset: offset to read | |
482 | * | |
483 | * This function must be used by drivers as their .read() #file_operations | |
484 | * method iff they use DRM events for asynchronous signalling to userspace. | |
485 | * Since events are used by the KMS API for vblank and page flip completion this | |
486 | * means all modern display drivers must use it. | |
487 | * | |
488 | * @offset is ignore, DRM events are read like a pipe. Therefore drivers also | |
489 | * must set the .llseek() #file_operation to no_llseek(). Polling support is | |
490 | * provided by drm_poll(). | |
491 | * | |
492 | * This function will only ever read a full event. Therefore userspace must | |
493 | * supply a big enough buffer to fit any event to ensure forward progress. Since | |
494 | * the maximum event space is currently 4K it's recommended to just use that for | |
495 | * safety. | |
496 | * | |
497 | * RETURNS: | |
498 | * | |
499 | * Number of bytes read (always aligned to full events, and can be 0) or a | |
500 | * negative error code on failure. | |
501 | */ | |
cdd1cf79 CW |
502 | ssize_t drm_read(struct file *filp, char __user *buffer, |
503 | size_t count, loff_t *offset) | |
c9a9c5e0 | 504 | { |
cdd1cf79 | 505 | struct drm_file *file_priv = filp->private_data; |
c9a9c5e0 | 506 | struct drm_device *dev = file_priv->minor->dev; |
9b2c0b7f | 507 | ssize_t ret; |
c9a9c5e0 | 508 | |
cdd1cf79 CW |
509 | if (!access_ok(VERIFY_WRITE, buffer, count)) |
510 | return -EFAULT; | |
c9a9c5e0 | 511 | |
9b2c0b7f CW |
512 | ret = mutex_lock_interruptible(&file_priv->event_read_lock); |
513 | if (ret) | |
514 | return ret; | |
515 | ||
cdd1cf79 | 516 | for (;;) { |
83eb64c8 CW |
517 | struct drm_pending_event *e = NULL; |
518 | ||
519 | spin_lock_irq(&dev->event_lock); | |
520 | if (!list_empty(&file_priv->event_list)) { | |
521 | e = list_first_entry(&file_priv->event_list, | |
522 | struct drm_pending_event, link); | |
523 | file_priv->event_space += e->event->length; | |
524 | list_del(&e->link); | |
525 | } | |
526 | spin_unlock_irq(&dev->event_lock); | |
527 | ||
528 | if (e == NULL) { | |
cdd1cf79 CW |
529 | if (ret) |
530 | break; | |
c9a9c5e0 | 531 | |
cdd1cf79 CW |
532 | if (filp->f_flags & O_NONBLOCK) { |
533 | ret = -EAGAIN; | |
534 | break; | |
535 | } | |
c9a9c5e0 | 536 | |
9b2c0b7f | 537 | mutex_unlock(&file_priv->event_read_lock); |
cdd1cf79 CW |
538 | ret = wait_event_interruptible(file_priv->event_wait, |
539 | !list_empty(&file_priv->event_list)); | |
9b2c0b7f CW |
540 | if (ret >= 0) |
541 | ret = mutex_lock_interruptible(&file_priv->event_read_lock); | |
542 | if (ret) | |
543 | return ret; | |
cdd1cf79 | 544 | } else { |
83eb64c8 CW |
545 | unsigned length = e->event->length; |
546 | ||
547 | if (length > count - ret) { | |
548 | put_back_event: | |
549 | spin_lock_irq(&dev->event_lock); | |
550 | file_priv->event_space -= length; | |
551 | list_add(&e->link, &file_priv->event_list); | |
552 | spin_unlock_irq(&dev->event_lock); | |
cdd1cf79 | 553 | break; |
83eb64c8 | 554 | } |
cdd1cf79 | 555 | |
83eb64c8 | 556 | if (copy_to_user(buffer + ret, e->event, length)) { |
cdd1cf79 CW |
557 | if (ret == 0) |
558 | ret = -EFAULT; | |
83eb64c8 | 559 | goto put_back_event; |
cdd1cf79 | 560 | } |
c9a9c5e0 | 561 | |
83eb64c8 | 562 | ret += length; |
1b47aaf9 | 563 | kfree(e); |
c9a9c5e0 | 564 | } |
c9a9c5e0 | 565 | } |
9b2c0b7f | 566 | mutex_unlock(&file_priv->event_read_lock); |
c9a9c5e0 | 567 | |
cdd1cf79 | 568 | return ret; |
c9a9c5e0 KH |
569 | } |
570 | EXPORT_SYMBOL(drm_read); | |
571 | ||
bcb877e4 DV |
572 | /** |
573 | * drm_poll - poll method for DRM file | |
574 | * @filp: file pointer | |
575 | * @wait: poll waiter table | |
576 | * | |
577 | * This function must be used by drivers as their .read() #file_operations | |
578 | * method iff they use DRM events for asynchronous signalling to userspace. | |
579 | * Since events are used by the KMS API for vblank and page flip completion this | |
580 | * means all modern display drivers must use it. | |
581 | * | |
582 | * See also drm_read(). | |
583 | * | |
584 | * RETURNS: | |
585 | * | |
586 | * Mask of POLL flags indicating the current status of the file. | |
587 | */ | |
1da177e4 LT |
588 | unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) |
589 | { | |
c9a9c5e0 KH |
590 | struct drm_file *file_priv = filp->private_data; |
591 | unsigned int mask = 0; | |
592 | ||
593 | poll_wait(filp, &file_priv->event_wait, wait); | |
594 | ||
595 | if (!list_empty(&file_priv->event_list)) | |
596 | mask |= POLLIN | POLLRDNORM; | |
597 | ||
598 | return mask; | |
1da177e4 | 599 | } |
b5e89ed5 | 600 | EXPORT_SYMBOL(drm_poll); |
2dd500f1 DV |
601 | |
602 | /** | |
4020b220 | 603 | * drm_event_reserve_init_locked - init a DRM event and reserve space for it |
2dd500f1 DV |
604 | * @dev: DRM device |
605 | * @file_priv: DRM file private data | |
606 | * @p: tracking structure for the pending event | |
607 | * @e: actual event data to deliver to userspace | |
608 | * | |
609 | * This function prepares the passed in event for eventual delivery. If the event | |
610 | * doesn't get delivered (because the IOCTL fails later on, before queuing up | |
611 | * anything) then the even must be cancelled and freed using | |
fb740cf2 DV |
612 | * drm_event_cancel_free(). Successfully initialized events should be sent out |
613 | * using drm_send_event() or drm_send_event_locked() to signal completion of the | |
614 | * asynchronous event to userspace. | |
2dd500f1 DV |
615 | * |
616 | * If callers embedded @p into a larger structure it must be allocated with | |
617 | * kmalloc and @p must be the first member element. | |
618 | * | |
4020b220 DV |
619 | * This is the locked version of drm_event_reserve_init() for callers which |
620 | * already hold dev->event_lock. | |
621 | * | |
2dd500f1 DV |
622 | * RETURNS: |
623 | * | |
624 | * 0 on success or a negative error code on failure. | |
625 | */ | |
4020b220 DV |
626 | int drm_event_reserve_init_locked(struct drm_device *dev, |
627 | struct drm_file *file_priv, | |
628 | struct drm_pending_event *p, | |
629 | struct drm_event *e) | |
2dd500f1 | 630 | { |
4020b220 DV |
631 | if (file_priv->event_space < e->length) |
632 | return -ENOMEM; | |
2dd500f1 DV |
633 | |
634 | file_priv->event_space -= e->length; | |
635 | ||
636 | p->event = e; | |
681047b4 | 637 | list_add(&p->pending_link, &file_priv->pending_event_list); |
2dd500f1 DV |
638 | p->file_priv = file_priv; |
639 | ||
4020b220 DV |
640 | return 0; |
641 | } | |
642 | EXPORT_SYMBOL(drm_event_reserve_init_locked); | |
643 | ||
644 | /** | |
645 | * drm_event_reserve_init - init a DRM event and reserve space for it | |
646 | * @dev: DRM device | |
647 | * @file_priv: DRM file private data | |
648 | * @p: tracking structure for the pending event | |
649 | * @e: actual event data to deliver to userspace | |
650 | * | |
651 | * This function prepares the passed in event for eventual delivery. If the event | |
652 | * doesn't get delivered (because the IOCTL fails later on, before queuing up | |
653 | * anything) then the even must be cancelled and freed using | |
654 | * drm_event_cancel_free(). Successfully initialized events should be sent out | |
655 | * using drm_send_event() or drm_send_event_locked() to signal completion of the | |
656 | * asynchronous event to userspace. | |
657 | * | |
658 | * If callers embedded @p into a larger structure it must be allocated with | |
659 | * kmalloc and @p must be the first member element. | |
660 | * | |
661 | * Callers which already hold dev->event_lock should use | |
662 | * drm_event_reserve_init() instead. | |
663 | * | |
664 | * RETURNS: | |
665 | * | |
666 | * 0 on success or a negative error code on failure. | |
667 | */ | |
668 | int drm_event_reserve_init(struct drm_device *dev, | |
669 | struct drm_file *file_priv, | |
670 | struct drm_pending_event *p, | |
671 | struct drm_event *e) | |
672 | { | |
673 | unsigned long flags; | |
674 | int ret; | |
675 | ||
676 | spin_lock_irqsave(&dev->event_lock, flags); | |
677 | ret = drm_event_reserve_init_locked(dev, file_priv, p, e); | |
2dd500f1 | 678 | spin_unlock_irqrestore(&dev->event_lock, flags); |
4020b220 | 679 | |
2dd500f1 DV |
680 | return ret; |
681 | } | |
682 | EXPORT_SYMBOL(drm_event_reserve_init); | |
683 | ||
684 | /** | |
685 | * drm_event_cancel_free - free a DRM event and release it's space | |
686 | * @dev: DRM device | |
687 | * @p: tracking structure for the pending event | |
688 | * | |
689 | * This function frees the event @p initialized with drm_event_reserve_init() | |
690 | * and releases any allocated space. | |
691 | */ | |
692 | void drm_event_cancel_free(struct drm_device *dev, | |
693 | struct drm_pending_event *p) | |
694 | { | |
695 | unsigned long flags; | |
696 | spin_lock_irqsave(&dev->event_lock, flags); | |
681047b4 DV |
697 | if (p->file_priv) { |
698 | p->file_priv->event_space += p->event->length; | |
699 | list_del(&p->pending_link); | |
700 | } | |
2dd500f1 | 701 | spin_unlock_irqrestore(&dev->event_lock, flags); |
1b47aaf9 | 702 | kfree(p); |
2dd500f1 DV |
703 | } |
704 | EXPORT_SYMBOL(drm_event_cancel_free); | |
fb740cf2 DV |
705 | |
706 | /** | |
707 | * drm_send_event_locked - send DRM event to file descriptor | |
708 | * @dev: DRM device | |
709 | * @e: DRM event to deliver | |
710 | * | |
711 | * This function sends the event @e, initialized with drm_event_reserve_init(), | |
712 | * to its associated userspace DRM file. Callers must already hold | |
713 | * dev->event_lock, see drm_send_event() for the unlocked version. | |
681047b4 DV |
714 | * |
715 | * Note that the core will take care of unlinking and disarming events when the | |
716 | * corresponding DRM file is closed. Drivers need not worry about whether the | |
717 | * DRM file for this event still exists and can call this function upon | |
718 | * completion of the asynchronous work unconditionally. | |
fb740cf2 DV |
719 | */ |
720 | void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e) | |
721 | { | |
722 | assert_spin_locked(&dev->event_lock); | |
723 | ||
3b24f7d6 DV |
724 | if (e->completion) { |
725 | /* ->completion might disappear as soon as it signalled. */ | |
726 | complete_all(e->completion); | |
727 | e->completion = NULL; | |
728 | } | |
729 | ||
1b47aaf9 GP |
730 | if (e->fence) { |
731 | fence_signal(e->fence); | |
732 | fence_put(e->fence); | |
733 | } | |
734 | ||
681047b4 | 735 | if (!e->file_priv) { |
1b47aaf9 | 736 | kfree(e); |
681047b4 DV |
737 | return; |
738 | } | |
739 | ||
740 | list_del(&e->pending_link); | |
fb740cf2 DV |
741 | list_add_tail(&e->link, |
742 | &e->file_priv->event_list); | |
743 | wake_up_interruptible(&e->file_priv->event_wait); | |
744 | } | |
745 | EXPORT_SYMBOL(drm_send_event_locked); | |
746 | ||
747 | /** | |
748 | * drm_send_event - send DRM event to file descriptor | |
749 | * @dev: DRM device | |
750 | * @e: DRM event to deliver | |
751 | * | |
752 | * This function sends the event @e, initialized with drm_event_reserve_init(), | |
753 | * to its associated userspace DRM file. This function acquires dev->event_lock, | |
754 | * see drm_send_event_locked() for callers which already hold this lock. | |
681047b4 DV |
755 | * |
756 | * Note that the core will take care of unlinking and disarming events when the | |
757 | * corresponding DRM file is closed. Drivers need not worry about whether the | |
758 | * DRM file for this event still exists and can call this function upon | |
759 | * completion of the asynchronous work unconditionally. | |
fb740cf2 DV |
760 | */ |
761 | void drm_send_event(struct drm_device *dev, struct drm_pending_event *e) | |
762 | { | |
763 | unsigned long irqflags; | |
764 | ||
765 | spin_lock_irqsave(&dev->event_lock, irqflags); | |
766 | drm_send_event_locked(dev, e); | |
767 | spin_unlock_irqrestore(&dev->event_lock, irqflags); | |
768 | } | |
769 | EXPORT_SYMBOL(drm_send_event); |